Moderate to severe obstructive sleep apnea (OSA), which encompasses apnea and hypopnea, is a serious disorder that affects millions of people on a daily basis such that their breathing is repeatedly stopped and started on an irregular basis thereby reducing oxygen levels in their blood stream. OSA is caused by complete or partial collapse of the pharynx during sleep. In particular, muscles in a patient's throat intermittently relaxes thereby blocking the upper airway while sleeping. Airflow into the upper airway can be blocked by the tongue moving to the back of the throat and covering a smaller than normal airway. Loss of airflow causes low oxygen saturation levels in the blood. Lack of adequate levels of oxygen can contribute to abnormal heart rhythms, heart attack, heart failure, high blood pressure, stroke, memory problems and increased accidents. Loss of air flow also causes unusual inter-thoracic pressure as a person tries to breathe with a blocked airway. Additionally, loss of sleep occurs when a person is awakened during an apneic episode.
Conventional treatment methods have been employed with varying degrees of success. For example, hypoglossal nerve stimulation (HGNS) has been used to move the tongue forward in the mouth to clear the airway. Some conventional HGNS therapy systems require the use of a cuff electrode wrapped around the hypoglossal nerve (HGN) to deliver therapy, as shown in U.S. Pat. No. 8,751,005 to Meadows et al. Implanting a cuff electrode is an invasive procedure requiring neuro-surgical skills. Additionally, there are occasions when nerve damage can occur due to attaching the cuff electrode to the nerve. Numerous other methods are disclosed for pacing neural tissue to address OSA such as U.S. Pat. No. 8,751,005 to Paul Meadows et al., US Pregrant Application No. US20020049479 to Pitts. US20140135868 to Bashyam, U.S. Pat. No. 8,909,341 to Gelfand et al., Inc., WO2010090852 to Lindquist et al., US Patent Application No. 20140323839 to Huntington et al. While conventional treatments have alleviated some of the OSA symptoms, disadvantages still exist with conventional devices and methods. It is therefore desirable to develop additional methods and systems that overcome the disadvantages associated with conventional OSA treatments.